Do any of the resident gurus know how to add additional language and a hyperlink to the verification email sent to new signups? Is it in the adduser.php file and if so what is the procedure?
Yes, you'll want to edit the adduser.php language file. You can do this through the admin section or you can directly edit the file on the server. Just look for the current text you want to change and change it to whatever you need/want it to say.
Can I just add to the line: [] $ubbt_lang['PASS_BODY'] = "Someone from the ip address '\$ip' registered the Login Name '\$Loginname'. The password for this Login Name is '\$pass'"; [/] and can I use straight html like [] <a href=page.html>link</a> [/] or will I have to escape characters with back slashes?
Yes, you can just add to that line. You don't need to escape the HTML tags, but if you add any double quotes you'll need to escape those. So if you wanted to add: